This set utilizes Minun's access to Encore and decent special bulk to make him an effective Nasty Plot Baton Passer. Encore allows Minun to lock Pokemon such as Registeel into a harmless move like Stealth Rock, effectively giving Minun a free turn afterward to set up. Since Minun can't set up on moderately powerful attackers even with a defensive EV spread, Encore is often extremely important to obtain a Nasty Plot boost. Thunderbolt gives Minun a reliable attack, which prevents him from being completely useless if he gets Taunted, and does decent damage after a Nasty Plot, even without Special Attack investment.
This EV spread is simple, but effective. A Timid nature and 252 Speed EVs are needed to tie with other max Speed base 95 Pokemon such as Houndoom. This can be important, as this gives Minun a 50% chance to Baton Pass the boost in a tight situation against them. 252 HP EVs boost Minun's overall bulk, and allow Minun to switch into a decent amount of weak special attacks. For example, this Minun will never be 2HKOed by 0 Special Attack Milotic's Surf, even after Stealth Rock. A more offensive spread can be used if you wish, but due to Minun's relatively poor defenses, he'll have an even harder time setting up than he does with the above EV spread.
Minun has a couple of other moves that he can use on this set. Agility is always useful to Baton Pass, but Nasty Plot is what makes Minun unique. It can, however, go over Thunderbolt if you wish. Magnet Rise can be an interesting option to Baton Pass, but like Agility, should only go over Thunderbolt. However, replacing Thunderbolt with either Agility or Magnet Rise leaves Minun rendered utterly useless by Taunt, so it isn't recommended. Hidden Power Ice would be a great option to hit Ground-types that Minun can't hit with Thunderbolt, but there is nothing that you can really replace on this set.
As this set's main goal is to Baton Pass Nasty Plot boosts, appropriate Baton Pass recipients are naturally important teammates. If possible, these Baton Pass recipients should also be able to deal with Ground-types. Therefore, Moltres, Mismagius, Rotom, and Sceptile are all excellent partners, as they benefit greatly from a Nasty Plot boost, and are immune or resistant to Ground-type attacks. All of these Pokemon pack incredible powerful after a Nasty Plot boost, and are fast enough to attempt a sweep.
Because both Minun and his Baton Pass recipients are specially-based, dedicated special sponges such as Chansey can pose problems. Even after a Nasty Plot boost, these Baton Pass recipients might still have a chance to be outstalled by Chansey. Dugtrio is a great choice to trap and KO Chansey. U-turn users such as Scyther and Swellow can also help weaken the opposing team, and scout for any Pokemon that may pose a problem to your Baton Pass recipient.